Compound properties such as "Aromatic Atoms count" and "sp3-Atoms count" are calculated via the "Add Compound Properties" entry in DataWarrior. Is there a document in which all the compound properties are defined? For example, I would like to know if hydrogen atoms are included in "Aromatic Atoms Count".

you are right that DataWarrior lacks a more detailled explanation of the properties. I will try to add that soon. On the other hand the counts are rather simple and often self explanatory. Hydrogen atoms are never considered, neither implicit nor explicit ones.